Carbon dioxide. Properties, production, application

Carbon dioxide is a substance that has many names: carbon monoxide (IV), carbon dioxide or carbon dioxide. It is also called coal anhydride. It is a completely colorless gas that does not smell, with an acidic taste. Carbon dioxide is heavier than air and poorly soluble in water. At a temperature below -78 degrees Celsius it crystallizes and becomes like snow.

From the gaseous state, this substance passes into a solid state, since it can not exist in a liquid state under atmospheric pressure. The density of carbon dioxide under normal conditions is 1.97 kg / m3 - 1.5 times higher than air density. Carbon dioxide in solid form is called "dry ice". In the liquid state, in which it can be stored for a long time, it passes with increasing pressure. Let us consider in detail this substance and its chemical structure.

Carbon dioxide, the formula of which is CO2, consists of carbon and oxygen, and it is obtained as a result of burning or decay of organic substances. Carbon monoxide is contained in the air and underground mineral springs. People and animals also emit carbon dioxide when breathing out air. Plants without illumination isolate it, and during photosynthesis intensively absorb. Thanks to the process of metabolism of cells of all living things, carbon monoxide is one of the main components of the surrounding nature.

This gas is not toxic, but if it accumulates in a large concentration, choking (hypercapnia) may begin, and if it lacks the opposite state develops - hypocapnia. Carbon dioxide transmits ultraviolet rays and reflects infrared rays . It is a greenhouse gas that directly affects global warming. This is due to the fact that the level of its content in the atmosphere is constantly growing, which leads to a greenhouse effect.

Carbon dioxide is produced commercially from smoky or furnace gases, or by decomposition of dolomite and limestone carbonates. The mixture of these gases is thoroughly washed with a special solution consisting of potassium carbonate. Then it passes into the hydrocarbonate and decomposes on heating, resulting in the release of carbon dioxide. Carbon dioxide (H2CO3) is formed from carbon dioxide dissolved in water, but in modern conditions it is obtained by other, more progressive methods. After the carbon dioxide is purified, it is compressed, cooled and pumped into cylinders.

In industry, this substance is widely and universally applied. They use it as a baking powder (for example, to make a dough) or as a preservative (E290). With the help of carbon dioxide produce a variety of tonic drinks and sodas, which are so loved not only by children, but also by adults. Carbon dioxide is used in the production of baking soda, beer, sugar, sparkling wines.

Carbon dioxide is also used in the production of effective extinguishers. With the help of carbon dioxide, an active medium is created, which is necessary for welding with wire. At a high temperature of the welding arc, carbon dioxide decomposes into oxygen and carbon monoxide. Oxygen reacts with the liquid metal and oxidizes it. Carbon dioxide in cans is used in pneumatic guns and pistols.

Aviamodelists use this substance as a fuel for their models. With the help of carbon dioxide, yields of crops grown in the greenhouse can be significantly increased. Also in the industry is widely used dry ice, in which food is preserved much better. It is used as a refrigerant in refrigerators, freezers, electric generators and other heat power plants.